Increasing attention has been directed toward early identification of factors that place children at a greater than average risk to later disorder. Prematurity is one such factor. It often involves central nervous system dysfunction as evidenced by neurologic, sensory, behavioral and intellectual deficits. Most evidence concerning the intellective deficits of prematures is based on tests administered to prematures during late infancy and during childhood. There is little evidence concerning the precursors to intellective abilities in premature infants at the perinatal stage. Also, there is no evidence as to whether intellective deficits of prematurity are due to immaturity or the organism at birth or due to medical problems associated with prematurity. Respiratory, cardiac and/or nutritional problems could cause insults to the premature's central nervous system. The different levels of maturity reached by the tactile, auditory and visual systems at the time of premature birth may determine the benefits or harm brought to these systems by the extrauterine environment. The differential interaction of the sensory modalities with the extrauterine environment may be a source of difficulty for the development of intellective function in prematures. The present study is an attempt to gather information relative to the above issues.